All Free Everyday Science MCQs with Answers

1921. The common refrigerant used in domestic Refrigerator is_____________?

• A. Neon
• B. Spirit
• C. Freon/Ammonia
• D. Methane

Explanation: Domestic refrigerators traditionally used Freon-type refrigerants, although many modern models use newer, less ozone-damaging alternatives. Ammonia is mainly associated with industrial refrigeration, so the combined option is an outdated but intended choice.

1922. Who invented the safety pin?

• A. Charles Goodbye
• B. steward Harshone
• C. Walter Hunt
• D. A.Rose

Explanation: Walter Hunt patented the modern safety pin in 1849, designing it with a clasp that protects the sharp point. The other names are not associated with this invention.

1923. Who developed the telegraph code?

• A. Andre Ampere
• B. Samuel Morse
• C. Joseph Henry
• D. Jean Fourier

Explanation: Samuel Morse developed the code used with the telegraph, now called Morse code. It represents letters and numbers through combinations of dots and dashes.

1924. Diesel engine was discovered by___________?

• A. Paul Muller
• B. Faraday
• C. Waldeyer
• D. Rudolf Diesel

Explanation: Rudolf Diesel developed the compression-ignition engine, which is therefore called the diesel engine. It ignites fuel using the heat produced by compressing air rather than a spark plug.

1925. How many elements are in Modern periodic table?

• A. 112
• B. 118
• C. 114
• D. 116Trying Interactive Physics Simulation Software

Explanation: There are currently 118 officially recognized chemical elements in the modern periodic table. Atomic numbers 113 to 118 completed the currently known seventh period.

1926. The unit to measure the quantity of Ozone in atmosphere is ?

• A. Dobson
• B. Cloning
• C. Dalton
• D. Colomb

Explanation: The Dobson unit measures the total amount of ozone in a vertical column of the atmosphere. Dalton measures atomic or molecular mass, whereas cloning is a biological process.

1927. Which of the following vitamin is known as Folate?

• A. vitamin B-6
• B. vitamin B-9
• C. vitamin B-2
• D. vitamin B-12

Explanation: Folate is vitamin B9, a water-soluble vitamin needed for DNA synthesis and red-blood-cell formation. Its deficiency is especially important during pregnancy because it can cause neural-tube defects.

1928. Which of the following is not a fat soluble vitamin?

• A. Vitamin A
• B. Vitamin D
• C. Vitamin B complex
• D. Vitamin K

Explanation: The B-complex vitamins are water-soluble and are not stored extensively in body fat. Vitamins A, D and K are fat-soluble vitamins.

1929. Which blood cells are called 'Soldiers' of the body?

• A. White Blood Cells
• B. Platelets
• C. Red Blood Cells
• D. None of the above

Explanation: White blood cells are called the body's soldiers because they identify and destroy pathogens and help coordinate immune defence. Red blood cells transport oxygen, while platelets mainly help blood clot.

1930. The protein content in wheat is approximately_______________?

• A. 6%
• B. 9%
• C. 12%
• D. 15%Purchasing Educational Biology Kits

Explanation: Wheat grain generally contains about 10 to 13 percent protein, so 12 percent is the usual approximate value. The amount varies with wheat variety and growing conditions.